Ventilator operating mechanism



Jan 19, 1932. MCKEE 1,842,041

VENTILATOR OPERATING MECHANISM (FOR GREENHOUSES Filed April 18. 1928Patented Jan. 19, 1932 "PAT-EN T F F'IC E P'H'itrr L. MCKEE,or-oir'reaco, nitmois VENTIIJATOR OPERATING MECHANISM (non Gnnmvnousns)Application 'filed' 'April 18,

My invention relates to operating mechanisms for ventilators'and thelike; and par ticularly to means adaptable for use in connection withthe operation of ventilator 5 sashes for greenhouses.

In general, one of the primary objects of my invention is to provide anefiiciently operable device for controlling the movement ofventilatorsashes and devices of like'nature, said operating mechanismbeing of such a nature as to permit the movement or displacement of aventilator sash within predetermined limits.

More specifically, an object of my present invention is to preventventilator sashes and the like which are operated through the agency ofchains or other flexible means from being opened beyond a predeterminedlimit, and to this end I propose to provide connecting link inassociation with the flexible actuating means or chain which will limitthe longitudinal movement of said chain.

A still further object of my invention is to provide a ventilatoractuating device which includes a flexible member or chain which isadapted to' be guided over suitable pulleys or sprockets, and to limitthe longitudinal movement of said flexible member or chain I propose toconnect one extremity of a link member to one of the reaches of saidchain, the opposite extremity of the connecting link being suitablysecured in a fixed position or secured to the other reach of said chain,the distance through which the chain may be moved, being determined bythe length and relative position of said connecting link.

In addition to the above mentioned characteristics, my inventioncontemplates the provision of a ventilator operating mechanism whichlends itself structurally for use in connection with greenhouseventilator sashes and to this end I provide a flexible actuating chainor cord disposed between a pair of pulleys or sprockets, the upperpulley or sprocket being operatively connected with a rack and piniondevice for opening and closing a ventilator sash, and the lower pulleyor sprocket being operatively connected with a manually operable drivingmechanism, and

1928. Serial No. 270,892.

to limit the longitudinal movement of the chain, I employ a flexiblelink connected between the'reaches of said ventilator actuating chain.

These and other objects will be more apparent from the followingdetailed description when considered in connection with the as beingsecured at one extremity to a porti on of the greenhouse frame.

Referring now in detail to the drawings wherein like numerals have beenemployed to designate similar parts throughout the vari ous fi ures, itwill be observed that one embodiment of my improved ventilator operatingmechanism includes an endless actuating means, designated generally bythe numeral 2, which is dispose-d between a pair of suitable rotarymembers or sprockets 4 and 6 positioned at upper and lower extremitiesrespectively of a suitable greenhouse frame member 8. This endlessactuating means includes a chain portion 10 which is guided by thesprocket 6 and another chain portion 12 which is guided by the sprocket6t. Strips 14 are interposed between extremities of the chain portions10 and 12 and it will be clear that in order to move the endlessactuating means it is only necessary to impart a rotary movement to thesprocket 6.

The sprocket 6 may be conveniently rotated through the agency of a handwheel 16, which is operatively connected to the sprocket 6 by means of asuitable worm wheel mechanism, indicated generally by the numeral 18,which is supported by means of a suitable clamping sleeve 20 upon theframe 8.

To limit the distance through which the endless actuating means 2 may bemoved in response to the manipulation of the hand wheel 16, I provide aflexible connecting means or link 22. in Figures 1 and 2 T have shownthis flexible connecting link connected between the reaches of ti echain 10. Obviously the limiting movement of the endless actuating meanswill be determined by the length of the connecting link. In Figure 3 lhave shown the flexible connecting link 22 as being connected at oneextrei'nity to one of the reaches of the chain 10 and the oppositeextremity connected or secured to the frame 8. This link 2:2 provides avery simple and effective means for limiting the movement or trav l )1the endless actuatin means and its practical adaptability will be moreapparent in Figure 1 wherein I have disoperating mechanism in greenhouseventilator closed my impro ed association with a sash 24.

This greenhouse ventilator sash is provided with a rack bar 26 which ispivoted at its upper extremity to the underside of the sash 2st andwhich is maintained in operative association with a pi 'on 28 throughthe agency of a suitable guiding device 30. The pinion 28 is mountedupon a shaft which alsocarries the sprocket t and it will be apparentthat when rotation is imparted to the sprocket 4 in a clockwisedirection, as viewed in Figure 1, the rack and pinion mechanism justdescribed serves to elevate or open the sash 24. Likewise when acounter-clockwise rotation is experienced by the sprocket 4, said sashwill be lowered into a closed position. The length of the flexible link22 is such that when the sash has been raised to a proper predeterminedposition, as shown in Figure 1, said link will be rendered taut andhence will prevent the further elevation of the sash. Experience hasshown that when the degree of movement of the endless flexible actuatingmeans is not controlled, attendants within the greenhouse inadvertentlycause the sash to be opened too far. By employing my convenientconnecting link, I am able to control the actuation of the sash andhence preclude the unsatisfactory results which have heretofore beenexperienced.

From the foregoing it will be appreciated that my invention provides avery simple, economical and effectively operable means whereby themovement of ventilator sashes and other devices of like nature may be effectively controlled. Obviously my invention is not limited to the useof any particular type of endless actuating means, nor is it limited toany particular type of connecting link. In other words, the sprocket andchain mechanism and the particular type of flexible link connectedtherewith is illustrative of one embodiment of my invention. Othermodifications and applications of my invention may be made withoutdeparting from the spirit and scope of the appended claims. The lengthof the flexible connecting link which I employ will obviously determinethe extent of movement which may be experienced by the endless conveyormeans and consequently the extent of upward displacement of theventilator sash. In this manner I am able to obviate the inconvenienceand injurious results whichv are experienced when the extent of movementof a sash actuating chain is not limited.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. In combination with an endless act-uating means, a link memberconnected between the reaches of said endless actuating means to preventthe movement thereof beyond a predetermined limit.

2. A device for limiting the movement of an endless actuating membercomprising a member adapted to be connected directly to said actuatingmember whereby movement of said actuating member is limited by saidsecond named member.

3. A device for limiting the movement of an endless chain actuatingmember comprising a flexible member adapted to be connected betweenreaches of said chain to prevent movement of said chain beyond apredetermined limit.

Tn witness whereof, I have hereunto subscribed my name.

PHILIP L. MOKEE.

